Process for the preparation of high activity carbon monoxide hydrogenation catalysts; the catalyst compositions, use of the catalysts for conducting such reactions, and the products of such reactions

ABSTRACT

A process for the preparation of a catalyst useful for conducting carbon monoxide hydrogenation reactions, especially Fischer-Tropsch reactions. The steps of the process begin with the activation, or reactivation, of a deactivated catalyst, or with the preparation and activation of a fresh catalyst. In accordance with the latter, the steps of the process comprise, first contacting, in one or more steps, a powder or preformed, particulate refractory inorganic support with a liquid, or solution in which there is dispersed or dissolved a compound, or salt of a catalytically active metal, or metals, to impregnate and deposit the metal, or metals, upon the support, or powder. The metal, or metals, impregnated support is calcined following each impregnation step to form oxides of the deposited metal, or metals. The calcined catalyst precursor is then treated with a solution of a chelating compound, preferably a poly- or multidentate chelating compound, sufficient to complex with, extract and remove a portion of the oxides of the metal, or metals. The catalyst is activated by reduction; suitably by contact with hydrogen. In the activation, or reactivation of a deactivated catalyst, the catalyst is first treated with the chelating compound to extract a portion of the oxides of the metal, or metals, and the catalyst is then reduced. In either event, the activated or reactivated catalyst has high activity, or high C 5 + selectivity, or both high activity and C 5 + selectivity in conducting carbon monoxide hydrogenation reactions. The productivity of the process is increased.

1. FIELD OF THE INVENTION

[0001] This invention relates to a process for the preparation of novel,highly active catalysts for conducting carbon monoxide hydrogenationreactions, especially Fischer-Tropsch reactions. It also relates to thecatalyst, to the process utilizing the catalyst, and to the product ofsuch process; particularly transportation fuels and lubricating oilsderived from synthesis gas.

2. BACKGROUND

[0002] The improvement of Fischer-Tropsch (F-T) catalysts, i.e.,catalysts useful for the production of petrochemicals and liquidtransportation fuels by hydrogenation of carbon monoxide, has been thesubject of ongoing research for some years; and this work continues.Early commercial work with the F-T process began in Germany in the1920's, and was continued, resulting in the SASOL plants of SouthAfrica. F-T synthesis is well documented in the technical and patentliterature. The Group VIII metals, e.g., ruthenium and the Iron GroupMetals such as iron and cobalt, have been used extensively as catalyticmetals in the production of F-T catalysts, and these metals have beenpromoted or modified with various other metals, and supported on varioussubstrates in formation of the catalysts.

[0003] Cobalt catalysts, particularly the promoted cobalt catalysts,e.g., those constituted of cobalt and rhenium, or cobalt, thoria andrhenium, supported on titania, or other titania-containing support havebeen found to exhibit high selectivity in the conversion of methanol tohydrocarbon liquids, or synthesis of hydrocarbon liquids from hydrogenand carbon monoxide as disclosed, e.g., in U.S. Pat. No. 4,568,663. Thecatalysts can be prepared by gellation or cogellation techniques, buttypically they are prepared by deposition of the metal, or metals, onthe previously pilled, pelleted, beaded, extruded, or sieved supportmaterial, or a powder by the impregnation method. In preparing thecomposite catalysts, the metals are deposited from solution on thesupport in preselected amounts to provide the desired absolute amountsand weight ratio of the respective metals, e.g., cobalt and rhenium.Suitably, e.g., the cobalt and rhenium are composited with the supportby contacting the support with a solution of a cobalt-containingcompound, or salt, or a rhenium-containing compound, or salt, e.g., anitrate, carbonate or the like. Optionally, cobalt and rhenium can beco-impregnated upon the support. The cobalt and rhenium compounds usedin the impregnation can be any organometallic or inorganic compoundswhich decompose to give cobalt and rhenium oxides upon calcination, suchas a cobalt, or rhenium nitrate, acetate, acetylacetonate, naphthenate,carbonyl, or the like. The amount of impregnation solution used shouldbe sufficient to impregnate the catalyst via the incipient wetnesstechnique, or sufficient to completely immerse the carrier, usually avolume of liquid ranging from about 1 to 20 times of the carrier byvolume, depending on the metal, or metals, concentration in theimpregnation solution. The impregnation treatment can be carried outunder a wide range of conditions including ambient or elevatedtemperatures. The catalyst, after impregnation, is dried, and calcined;suitably by contact with oxygen, air or other oxygen-containing gas attemperature sufficient to oxidize the metal, or metals; e.g., to convertcobalt to Co₃O₄. The catalyst, or catalyst precursor, is then reducedand activated by contact of the oxidized metal, or metals, withhydrogen, or hydrogen-containing gas.

[0004] The reduced catalysts, e.g., cobalt catalyst, and cobalt catalystpromoted with other metals, have been found to provide relatively highselectivity, activity and activity maintenance in methanol conversion,and in the conversion of hydrogen and carbon monoxide to distillatefuels; predominantly C₅+ linear paraffins and olefins, with lowconcentrations of oxygenates. Nonetheless, there remains a pressing needfor F-T catalysts of yet higher activity; particularly more activecatalysts capable of producing transportation fuels and lubricants ofhigh quality at good selectivity and high levels of productivity.

3. THE INVENTION

[0005] This need and others are achieved in accordance with the presentinvention which embodies the activation, or reactivation of adeactivated catalyst, or the preparation and activation of a freshcatalyst. The process requires, in the preparation of the catalyst,contacting a powder or preformed particulate solids support, suitably arefractory inorganic oxide support, preferably a crystallinealuminosilicate zeolite, natural or synthetic, alumina, silica,silica-alumina or titania in one or a series of two or more steps with aliquid, or solution, suitably an aqueous solution containing a compound,or salt of a catalytic metal, or metals, preferably a Group VIIB orGroup VIII metal, or metals, of the Periodic Table of the Elements(Sargent-Welch Scientific Company; Copyright 1968) to impregnate anddeposit the metal, or metals, upon the powder or support. Theimpregnated powder or support is then calcined. Generally, two to fouror more metal impregnations, with intermediate calcination of the metal,or metals, impregnated support is preferred, and is sufficient todeposit from about 5 percent to about 70 percent, preferably from about10 percent to about 30 percent metallic metal, or metals, upon thesupport or powder, based upon the total weight (wt. %) of the calcinedcatalyst.

[0006] An inactive or deactivated catalyst, or the calcined catalyst, orcatalyst precursor, is then contacted, and treated with a solution of achelating compound, preferably a poly- or multidentate chelatingcompound, sufficient to complex with, extract and remove some of themetal atoms present in the oxides, or reduced metal particles, andincrease the activity or C₅+ selectivity, or both the activity and C₅+selectivity of the catalyst in its use, after reduction, in thehydrogenation of carbon monoxide, or conduct of Fischer-Tropschsynthesis reactions. The extraction, and removal of some of thecatalytic metal from the catalyst, or calcined catalyst precursor, inthis manner to increase the activity of the catalyst is indeed asurprising effect since past experience has shown that the activity of acatalyst constituted of a given metal, e.g., cobalt, is directly relatedto the amount of metallic metal, e.g., metallic cobalt, contained on thecatalyst; the greater the amount of metallic cobalt contained on thecatalyst, after reduction, the greater the activity of the catalyst inconducting carbon monoxide hydrogenation reactions, especially inconverting synthesis gas, or mixtures of hydrogen and carbon monoxide,to C₅+ hydrocarbons. However, it is found that treatment of adeactivated, or calcined metal, or metals, loaded catalyst or catalystprecursor, with the chelating compound sufficient to extract, or removethe metal, or metals, to leave from about 1 percent to about 80 percent,preferably from about 25 percent to about 75 percent, of the metal, ormetals present before the extraction, measured as metallic metal, willincrease the activity of the catalyst, after reduction, as much as about10 percent, and higher, and often as much as 25 percent; activity valuesconsiderably in excess of those which can be achieved by reducing thedeactivated or calcined catalysts without first treating thedeactivated, or calcined catalysts with the chelating compound.Moreover, the C₅+ selectivity of the catalyst is increased, resulting inas much as a four-fold increase in productivity.

[0007] In impregnating the support to form a catalyst, it is believedthat the metal, e.g., cobalt, initially deposits within the pores of thesupport, and is then laid down along the peripheral surface between thepores, bridging over and covering some of the previously open pores, orpore mouths. On calcination the cobalt is converted to Co₃O₄. Reductionof the cobalt oxide component e.g., with hydrogen, as in conventionalpractice produces a catalyst active for the hydrogenation of carbonmonoxide, or conversion of a synthesis gas to C₅+ hydrocarbons. On theother hand however, if before reducing the catalyst with hydrogen, thesame catalyst, or catalyst precursor is contacted, and treated byextraction with the chelating compound, e.g., sodium ethylene diaminetetraacetic acid, a portion of the Co₃O₄ deposits are removed from thepores to form a catalyst which, on reduction, albeit it contains alesser amount of cobalt, is considerably more active for thehydrogenation of carbon monoxide, or conversion of a synthesis gas toC₅+ hydrocarbons, than the more highly metal loaded catalyst, orcatalyst precursor not so treated with the chelating compound. In otherwords, the activity, or C₅+ selectivity, or both the activity and C₅+selectivity, is higher than that of the more highly metal loadedcatalyst, or catalyst precursor not so treated with the chelatingcompound.

[0008] An inactive catalyst, or catalyst deactivated in having beenpreviously used in a carbon monoxide hydrogenation operation, or freshlyprepared support with which a metal, or metals, has been composited, inthe practice of this invention, is thus treated as follows: It iscontacted, and leached with a liquid, or solution containing any of avariety of chelating compounds, preferred of which are poly- ormultidentate chelating compounds. Poly- or multidentate chelatingcompounds suitable for the practice of this invention are characterizedas having a denticity of two or more, preferably six, functionalcoordinating groups or ligands which form chelated metal cations withthe oxidized catalytic metal, or metals, of the catalyst or catalystprecursor. The poly- or multidentate chelating compound, or compounds,is dispersed, or dissolved in the liquid medium, suitably an aqueousmedium, in concentration sufficient to complex with, dissolve and removechelated metal cations of the catalytic metal, or metals, from the poresof the support. On reduction, e.g., by contact with hydrogen, theactivity of the catalyst contacted and treated with the chelatingcompound will be greater than a catalyst otherwise similar except thatit has not been treated with the chelating compound, or compounds,albeit lower in content of total metallic metal. Whereas the reason forthis increased activity is not fully understood, it is believed thatbetter diffusion through the pores is obtained by treatment of thecatalyst or catalyst precursor with the chelating compound. Moreover,the surface area of the metallic crystallites may be increased by thetreatment.

4. DETAILED DESCRIPTION

[0009] Further details describing the preparation and activation of afresh catalyst, and the activation, or reactivation, of an inactive ordeactivated catalyst is given as follows: First, in the preparation of afresh catalyst, the precursor catalyst composite is prepared by

[0010] (1) initially contacting a powder or preformed particulate solidssupport, suitably but not limited to carbides, nitrides, alumina andzirconia, but particularly a refractory inorganic oxide support,preferably silica or silica-alumina, and more preferably titania, andincluding crystalline aluminosilicates or zeolites, natural andsynthetic, particularly those of large pore size ranging up to about 100Angstrom Units (Å), this including A zeolite, X zeolite, Y zeolite,mordenite, ZSM-zeolite, silicalites, MCM, ALPO, SAPO and the like, witha liquid, or solution, containing a compound, or salt of a catalyticmetal, or metals, suitably a Group IIIB, IVB, VB, VIB, VIIB or VIIImetal, or metal of the lanthanum or actinium series, preferably a GroupVIIB or VIII metal, especially an Iron Group metal, i.e., a compound, orsalt of iron, cobalt, nickel, or mixture thereof, in one, or in a seriesof steps: preferably two to four steps. Compounds suitable as sources ofthe Iron Group metal are, e.g., cobalt nitrate, cobaltoushydroxyquinone, cobalt acetate, cobalt carbonyls, iron acetate, nickelacetate, nickel acetylacetonate, nickel naphthenate, and the like.Suitably, a promoter metal is similarly added, serially orsimultaneously from a solution containing a salt or compound of themetal, e.g., ruthenium or rhenium, to promote, or modify the activity,or selectivity, of a given catalyst for conducting a carbon monoxidehydrogenation, or F-T reaction. For example, although an Iron Groupmetal/titania catalyst is highly active for the conversion of synthesisgas, or highly selective for the production of C₅+ hydrocarbons, orboth, an additional metal, or metals, can be included as a promoter, ormodifier if desired. Ruthenium or other Group VIII noble metal, rheniumor the like may thus be included, the amount thereof ranging up to a1:12 ratio of promoter metal:Iron Group metal (wt. basis), preferably upto a 1:80 ratio of promoter metal to Iron Group metal (wt. basis). Thus,a Ru:Co ratio of about 1:80 and a Re:Co ratio of about 1:12 provideshighly active catalysts. In general, it is preferred to codeposit thepromoter metal, or metals, onto the support simultaneously with thecatalytic metal, or metals, e.g., rhenium and an Iron Group metal, ormetals. This can be done, e.g., by using a compound, or salt of thepromoter metal, or metals, added with a compound, or salt of thecatalytic metal, or metals, dissolved in the same solvent; or thepromoter metal, or metals, may be deposited after deposition of the IronGroup metal, or metals, by dissolving a compound, or salt of thepromoter metal, or metals, in a different solution and impregnating thepreformed Iron Group metal/silica catalyst composite. Water is thepreferred dispersing agent, or solvent, but a wide variety of organic,or hydrocarbons, may also be suitable as dispersing agents, or solventsfor dispersing or dissolving the salt of the Iron Group metal, ormetals, and added promoter metal, or metals. Exemplary of selectivelyuseful solvents are straight chain, branched chain or cyclic aliphatichydrocarbons, saturated or unsaturated, substituted or unsubstituted,such as hexane, cyclohexane, methyl cyclohexane, and the like; aromatichydrocarbons substituted or unsubstituted, such as benzene, toluene,xylenes, ethylbenzene, cumene, and the like. If desired, the impregnatedsupport may be dried. The drying step, if employed, is conducted attemperature ranging preferably from about ambient to about 120° C. Thedrying step is conducted at pressures below atmospheric, aboveatmospheric, or at atmospheric or ambient pressure.

[0011] The metal, or metals, e.g., iron, cobalt or nickel, can be loadedupon a solids support component, e.g., a catalyst formed by compositingthe metal, or metals, with titania, or a zeolite, in concentrationsranging from about 5 percent to about 70 percent, and greater,preferably from about 10 percent to about 30 percent, measured aselemental metal, based on the total weight of the catalyst [wt. %; drybasis]. The metal, or metals, can be loaded upon, and effectivelyextracted pursuant to the practice of this invention from powders orsolids supports having a wide range of pore sizes, but has been foundparticularly effective in treating supports of average pore radius belowabout 100 Å. A preferred property of the support is that it have anaverage pore radius ranging between about 15 Å and 40 Å, more preferablyfrom about 20 Å to about 35 Å. Typically, the metal, or metals, iscomposited with the support by impregnation of the support up to orbeyond the point of incipient wetness.

[0012] (2) The metal, or metals, impregnated support is then calcined,and the metal, or metals, component thereof oxidized and the metal, ormetals converted to an oxide by heating in an oxidizing atmosphere attemperatures ranging from about 100° C. to about 700° C., preferablyfrom about 150° C. to about 450° C.

[0013] (3) Optionally, and preferably, steps (1) and (2), supra, arerepeated in seriatim, and this sequence of treatments can be repeatedone or more additional times, generally from about 2 to about 4 or moretimes, until the desired amount of the metal, or metals, has been loadedonto the catalyst.

[0014] An inactive or deactivated catalyst, e.g., such as one removedfrom an operating F-T reactor unit, or the precursor catalyst from Step(2) or Step (3), or support containing the metal, or metals, oxidecomponent is

[0015] (4) activated by contact, and treatment with a solution of achelating compound, suitably a poly- or multidentate chelating compound,or compounds, sufficient to complex with, extract and remove some of themetal oxide(s) to activate, or increase the activity, or C₅+selectivity, or both the activity and C₅+ selectivity of the catalystwhen reduced and used in the hydrogenation of carbon monoxide, orconduct of F-T reactions. Exemplary of chelating compounds suitable forthis purpose are nitrogen, or oxygen, or nitrogen and oxygen containingcompounds which contain chelating ligands (i.e., functional coordinatinggroups which have one or more pairs of electrons available for theformation of coordinate bonds), preferably those having a denticity ofat least two, and more preferably six or more. The solvent for thechelating compound is one which has the capacity to dissolve, orsolubilize both the chelating agent and the metal complex formed duringthe extraction. Molten wax and water are preferred solvents, buthydrocarbon solvents can be used. The chelated metal compound chelateswith the metal atoms present in the oxides, or reduced metal particles,becomes solubilized in the solution, and is extracted by the solutionand removed from the support.

[0016] The preferred chelating metal compound that is used for theextraction of a metal, e.g., cobalt, must thus include at least onepolydentate ligand, and preferably the total denticity of thepolydentate ligand, or compound, will be at least two, and preferablyrange from about two to six. Thus, e.g., where the denticity of acompound is six, it may contain one monodentate ligand and anotherligand having a denticity of five; three bidentate ligands; a bidentateand a quadridentate ligand; or two tridentate ligands. Preferredcompounds contain three bidentate or two tridentate ligands,particularly the latter. Typical ligands for extraction of catalyticmetals are, e.g., carboxylic acids, ketones, aldehydes, alcohols,ethers, and esters having oxygen and amine or nitrogen-containingheterocycles. For example, the following exemplifies common multidentateligands useful for the extraction of cobalt ions, to wit: ethylenediamines, alkyl diamines, diethylenetriamines, dialkyltriamines,acetylacetone, alkyl dicarboxylic acids and alkali salts of carboxylicacids. Exemplary of preferred poly- or multidentate compounds suitablefor this purpose are the ammonium and alkali salts of compounds havingthe formula:

[0017] wherein

[0018] A is an integer ranging from 1 to about 6, preferably 1; B and C.are integers defining the number of carboxyl groups associated with N,

[0019] B being an integer ranging from 0 to 2, and

[0020] C an integer ranging from 0 to 2;

[0021] with the sum of

[0022] B and C. ranging from 2 to 4, preferably 4.

[0023] Exemplary of such multidentate chelating compounds are ethylenediamine diacetic acid, ethylene diamine tetraacetic acid, diethylenediamine diacetic acid, tetraethylene diamine diacetic acid andtetraethylene diamine tetraacetic acid. Of such compounds, ethylenediamine tetraacetic acid is preferred.

[0024] The poly- or multidentate liganous compound, or compounds, e.g.,an ammonium or alkali containing salt (a salt of NH₄, Na, K, Li or thelike) is dispersed, or dissolved in a liquid in concentration rangingfrom about 0.001 percent to about 20 percent, preferably from about 0.01percent to about 10 percent, based on the total weight of the chelatingcompound, or compounds, and the liquid; preferably molten wax or water,though generally any liquid in which both the chelating agent and theextracted metal complex will solubilize is adequate as a solvent.

[0025] (5) The catalyst, or catalyst precursor, after extraction withthe chelating agent is reduced; suitably by contact with hydrogen or ahydrogen-containing gas, thus activating the catalyst.

Hydrocarbon Synthesis

[0026] In conducting the preferred Fischer-Tropsch, or F-T synthesisreaction, a mixture of hydrogen and carbon monoxide is reacted over anIron Group metal catalyst, e.g., a cobalt or ruthenium catalyst, toproduce a waxy product which can be separated in various fractions,suitably a heavy or high boiling fraction and a lighter or low boilingfraction, nominally a 700° F.+ (372° C.+) reactor wax and a 700° F.−(372° C.−) fraction. The latter, or 700° F.− (372° C.−) fraction, can beseparated into (1) a F-T Cold separator liquid, or liquid nominallyboiling within a range of about C₅-500° F. (260° C.), and (2) a F-T hotseparator liquid, or liquid nominally boiling within a range of about500° F.-700° F. (260° C. 372° C.). (3) The 700° F.+ (272° C.+) stream,with the F-T cold and hot separator liquids, constitute raw materialsuseful for further processing.

[0027] The F-T synthesis process is carried out at temperatures of about160° C. to about 325° C., preferably from about 190° C. to about 260°C., pressures of about 5 atm to about 100 atm, preferably about 10-40atm and gas hourly space velocities of from about 300 V/Hr/V to about20,000 V/Hr/V, preferably from about 500 V/Hr/V to about 15,000 V/Hr/V.The stoichiometric ratio of hydrogen to carbon monoxide in the synthesisgas is about 2.1:1 for the production of higher hydrocarbons. However,the H/CO₂ ratios of 1:1 to about 4:1, preferably about 1.5:1 to about2.5:1, more preferably about 1.8:1 to about 2.2:1 can be employed. Thesereaction conditions are well known and a particular set of reactionconditions can be readily determined by those skilled in the art. Thereaction may be carried out in virtually any type reactor, e.g., fixedbed, moving bed, fluidized bed, slurry, bubbling bed, etc. The waxy orparaffinic products from the F-T reactor are essentially non-sulfur,non-nitrogen, non-aromatics containing hydrocarbons. This is a liquidproduct which can be produced and shipped from a remote area to arefinery site for further chemically reacting and upgrading to a varietyof products, or produced and upgraded to a variety of products at arefinery site. For example, the hot separator and cold separatorliquids, respectively, C₄-C₁₅ hydrocarbons, constitute high qualityparaffin solvents which, if desired can be hydrotreated to remove olefinimpurities, or employed without hydrotreating to produce a wide varietyof wax products. The reactor wax, or C₁₆+ liquid hydrocarbons from theF-T reactor, on the other hand, can be upgraded by varioushydroconversion reactions, e.g., hydrocracking, hydroisomerization,catalytic dewaxing, isodewaxing, reforming, etc. or combinationsthereof, to produce (i) fuels, i.e., such as stable, environmentallybenign, non-toxic mid-distillates, diesel and jet fuels, e.g., lowfreeze point jet fuel, high cetane jet fuel, etc., (ii) lubes, orlubricants, e.g., lube oil blending components and lube oil base stockssuitable for transportation vehicles, (iii) chemicals and specialtymaterials, e.g., non-toxic drilling oils suitable for use in drillingmuds, technical and medicinal grade white oils, chemical raw materials,monomers, polymers, emulsions, isoparaffinic solvents, and variousspecialty products.

(I) Maximum Distillate Option A

[0028] The reactor wax, or 700° F.+ (372° C.+) boiling fraction from theF-T reactor, with hydrogen, is passed directly to a hydroisomerizationreactor, HI, operated at the following typical and preferred HI reactionconditions, to wit: HI Reactor Conditions Typical Range Preferred RangeTemperature, °F. (°C.) 300-800 (148-427) 550-750 (286-398) TotalPressure, psig  0-2500  300-1200 Hydrogen Treat Rate, 500-5000 2000-4000SCF/B

[0029] While virtually any catalyst useful in hydroisomerization orselective hydrocracking may be satisfactory for this operation, somecatalysts perform better than others. For example, catalysts containinga supported Group VIII noble metal, e.g., platinum or palladium, areparticularly useful as are catalysts containing one or more Group VIIIbase metals, e.g., nickel, cobalt, in amounts of about 0.5-20 wt %,which may or may not also include a Group VI metal, e.g., molybdenum, inamounts of about 1-20 wt %. The support for the metals can be anyrefractory oxide or zeolite or mixtures thereof. Preferred supportsinclude silica, alumina, silica-alumina, silica-alumina phosphates,titania, zirconia, vanadia and other Group III, IV, VA or VI oxides, aswell as Y sieves, such as ultrastable Y sieves. Preferred supportsinclude alumina and silica-alumina where the silica concentration of thebulk support is less than about 50 wt %, preferably less than about 35wt %.

[0030] A preferred catalyst has a surface area in the range of about180-400 m²/gm, preferably 230-350 m²/gm, and a pore volume of 0.3 to 1.0ml/gm, preferably 0.35 to 0.75 ml/gm, a bulk density of about 0.5-1.0g/ml, and a side crushing strength of about 0.8 to 3.5 kg/mm.

[0031] The preferred catalysts comprise a non-noble Group VIII metal,e.g., iron, nickel, in conjunction with a Group IB metal, e.g., copper,supported on an acidic support. The support is preferably an amorphoussilica-alumina where the alumina is present in amounts of less thanabout 30 wt %, preferably 5-30 wt %, more preferably 10-20 wt %. Also,the support may contain small amounts, e.g., 20-30 wt %, of a binder,e.g., alumina, silica, Group IVA metal oxides, and various types ofclays, magnesia, etc., preferably alumina. The catalyst is prepared bycoimpregnating the metals from solutions onto the support, drying at100-150° C., and calcining in air at 200-550° C.

[0032] The preparation of amorphous silica-alumina microspheres forsupports is described in Ryland, Lloyd B., Tamele, M. W., and Wilson, J.N., Cracking Catalysts, Catalysis: Volume VII, Ed. Paul H. Emmett,Reinhold Publishing Corporation, New York, 1960, pp. 5-9.

[0033] The Group VIII metal is present in amounts of about 15 wt % orless, preferably 1-12 wt %, while the Group IB metal is usually presentin lesser amounts, e.g., 1:2 to about 1:20 ratio respecting the GroupVIII metal. A typical catalyst is shown below: Ni, wt % 2.5-3.5 Cu, wt %0.25-0.35 Al₂O₃—SiO₂ 65-75 Al₂O₃(binder) 25-30 Surface Area 290-355m²/gm Pour Volume (Hg) 0.35-0.45 ml/gm Bulk Density 0.58-0.68 g/ml

[0034] The 700° F.+ (372° C.+) conversion to 700° F.− (372° C.−) in thehydroisomerization unit ranges from about 20-80%, preferably 20-50%,more preferably about 30-50%. During hydroisomerization essentially allolefins and oxygen containing materials are hydrogenated.

[0035] In a preferred option, both the cold separator liquid, i.e., theC₅-500° (260° C.) boiling fraction, and the hot separator liquid, i.e.,the 500° F.-700° F. (260° C.-372° C.) boiling fraction, are hydrotreatedin a hydrotreated reactor, H/T, at hydrotreating conditions, the H/Tproduct is combined with the HI product, and passed to a fractionator.The following describes the typical and preferred H/T reactionconditions, to wit: H/T Conditions Typical Range Preferred RangeTemperature, °F. (°C.) 200-750 (94-398) 350-600 (175-315) TotalPressure, psig 100-1500 300-750  Hydrogen Treat Rate, SCF/B 100-5000500-1500

[0036] Suitable hydrotreating catalysts include those which arecomprised of at least one Group VIII metal, preferably Fe, Co and Ni,more preferably Co and/or Ni, and most preferably Ni; and at least oneGroup VI metal, preferably Mo and W, more preferably Mo, on a highsurface area support material, preferably alumina. Other suitablehydrotreating catalysts include zeolitic catalysts, as well as noblemetal catalysts where the noble metal is selected from Pd and Pt. One,or more than one type of hydrotreating catalyst may be used in the samebed. The Group VIII metal is typically present in an amount ranging fromabout 2 to 20%, preferably from about 4 to 12%, based on the totalweight of the catalyst (wt.%, dry basis). The Group VI metal willtypically be present in an amount ranging from about 5 to 50 wt. %,preferably from about 10 to 40 wt. %, and more preferably from about 20to 30 wt.%.

[0037] Gas and C₅-250° F. (121° C.) condensate streams are recoveredfrom the fractionator. After separation and removal of the C₅-250° F.(121° C.) material, a 250° F.-700° F.− (121° C.-372° C.−) diesel fuel ordiesel fuel blending component is recovered from the fractionator. A700° F.+ (372° C.+) product component that is recovered is suitable as alube or lube oil blending component.

[0038] The diesel material recovered from the fractionator has theproperties shown below:

[0039] paraffins at least 95 wt %, preferably at least 96 wt %, morepreferably at least 97 wt %, still more preferably at least 98 wt %, andmost preferably at least 99 wt %. iso/normal ratio about 0.3 to 3.0,preferably 0.7-2.0; sulfur £50 ppm (wt), preferably nil; nitrogen £50ppm (wt), preferably £20 ppm, more preferably nil; unsaturates £2 wt %;(olefins and aromatics) oxygenates about 0.001 to less than 0.3 wt %oxygen water-free basis.

[0040] The iso paraffins which are present are largely mono methylbranched, and the product contains nil cyclic paraffins, e.g., nocyclohexane.

[0041] The 700° F.− (372° C.−) fraction is rich in oxygenates, and e.g.,95% of the oxygenates, are contained in this lighter fraction. Further,the olefin concentration of the lighter fraction is sufficiently low asto make olefin recovery unnecessary; and further treatment of thefraction for olefins is avoided.

[0042] These diesel fuels generally have the properties of high cetanenumber, usually 50 or higher, preferably at least about 60, morepreferably at least about 65, lubricity, oxidative stability, andphysical properties compatible with diesel pipeline specifications.

[0043] The product can be used as a diesel fuel per se or blended withother less desirable petroleum or hydrocarbon containing feeds of aboutthe same boiling range. When used as a blend, the product can be used inrelatively minor amounts, e.g., 10% or more for significantly improvingthe final blended diesel product.

[0044] Although, this material will improve almost any diesel product,it is especially useful in blending with refinery diesel streams of lowquality. Typical streams are raw or hydrogenated catalytic or thermallycracked distillates and gas oils.

Option B

[0045] Optionally, the cold separator liquid and hot separator liquid isnot subjected to any hydrotreating. In the absence of hydrotreating ofthe lighter fractions, the small amount of oxygenates, primarily linearalcohols, in this fraction can be preserved, though oxygenates in theheavier reactor wax fraction are eliminated during thehydroisomerization step. Hydroisomerization serves to increase theamount of iso paraffins in the distillate fuel and helps the fuel tomeet pour point and cloud point specifications, although additives maybe employed for these purposes.

[0046] The oxygen compounds that are believed to promote lubricity maybe described as having a hydrogen bonding energy greater than thebonding energy of hydrocarbons (the energy measurements for variouscompounds are available in standard references); the greater thedifference, the greater the lubricity effect. The oxygen compounds alsohave a lipophilic end and a hydrophilic end to allow wetting of thefuel.

[0047] Preferred oxygen compounds, primarily alcohols, have a relativelylong chain, i.e., C₁₂+, more preferably C₁₂-C₂₄ primary linear alcohols.

[0048] The amount of oxygenates present is rather small, but only asmall amount of oxygenates as oxygen on a water free basis is needed toachieve the desired lubricity, i.e., at least about 0.001 wt % oxygen(water free basis), preferably 0.001-0.3 wt % oxygen (water free basis),more preferably 0.0025-0.3 wt % oxygen (water free basis).

Option C

[0049] As a further option, all or preferably a portion of the coldseparator liquid can be subjected to hydrotreating while the hotseparator liquid and the reactor is hydroisomerized; the wider cuthydroisomerization eliminating the fractionator vessel. However, thefreeze point of the jet fuel product is compromised to some extent.Preferably, the C₅-350° F. (175° C.) portion of the cold separatorliquid is hydrotreated, while the 350° F.+ (175° C.+) material isblended with the hot separator liquid and the reactor wax andhydroisomerized. The product of the HI reactor is then blended with thehydrotreated C₅-350° F. (175° C.) product and recovered.

Option D

[0050] In a fourth option, a split-feed flow scheme is provided whichcan produce a jet fuel capable of meeting a jet A-1 freeze pointspecification. In this option, the hot separator liquid and the reactorwax is hydroisomerized and the product recovered. The cold separatorliquid, and optionally any residual 500° F.− (260° C.−) components aftersubjecting the hot separator liquid and reactor wax to treatment in awax fractionator prior to hydroisomerization, is subjected tohydrotreating. The hydrotreated product is separated into a (a) C₅-350°F. (175° C.) product which is recovered, and a 350° F.+ (175° C.)product which is hydroisomerized and the hydroisomerized product thenalso recovered. These products can be blended together to form a jetfuel meeting a jet A-1 freeze point specification.

(II) Production of Maximum Diesel

[0051] The three streams from the F-T reactor constituting the syncrude,viz. 1) the cold separator liquid (C₅-500° F.), 2) hot separator liquid(500° F.-700° F.), and 3) reactor wax (700° F.+) are each treated inaccordance with certain options for producing the maximum amount of adiesel fuel as follows:

Option A: (Single Reaction Vessel: Wax Hydroisomerizer)

[0052] The reactor wax from the F-T reactor is passed, with hydrogen, toa wax hydroisomerizer. The other two streams from the F-T reactor, i.e.,the cold separator liquid and the hot separator liquid, are combinedwith the product from the hydroisomerizer, and the total mixture ispassed to a fractionation column where it is separated into light gases,naphtha, and a 700° F.− (372° C.−) distillate while a 700° F.+ (372°C.+) stream is recycled to extinction in the hydroisomerizer.

[0053] The catalysts used to conduct the wax hydroisomerization reactionare described in subsection (I) Maximum Distillate, Option A.

[0054] The conditions employed for conducting the wax hydroisomerizationreaction are described in subsection (I) Maximum Distillate, Option A.

Option B: (Two Vessel System: Wax Hydroisomerizer and Hydrotreater)

[0055] In this Option B, the reactor wax treating scheme described formaximum diesel in accordance with option A is unchanged, but in thisinstance both the cold separator liquid and hot separator liquid arehydrotreated at hydrotreating conditions, the product therefrom is thenmixed with the product of the wax hydroisomerizer, and the total mixturefractionated to recover light gases, naphtha and distillate.

[0056] The hydrotreating catalyst used in conducting the hydrogenationreaction is described in subsection (I) Maximum Distillate, Option A.

[0057] The conditions employed in conducting the hydrotreating reactionis described in subsection (I) Maximum Distillate, Option A.

Option C: (One Vessel: A Wax Hydroisomerizer)

[0058] In accordance with this option, both the cold separator liquidand the reactor wax are hydroisomerized, the hot separator liquid ismixed with the product from the hydroisomerizer, and the total mixtureis passed to a fractionater where it is separated into light gases,naphtha and distillate. A 700° F.+ (372° C.+) fraction is recycled toextinction in the wax hydroisomerizer.

[0059] The catalyst used to conduct the wax hydroisomerization reactionis described in subsection (I) Maximum Distillate, Option A.

[0060] The conditions employed in conducting the hydroisomerizationreaction is described in subsection (I) Maximum Distillate, Option A.

(III) Production of Maximum Lube (Two reaction vessels; aHydroisomerizer and a Catalytic Dewaxing Unit)

[0061] The reactor wax, or 700° F.+ boiling fraction, and the hotseparator liquid, or 500° F.-700° F. boiling fraction, from the F-Treactor are reacted in a hydroisomerizer and the product therefrompassed to a fractionator column wherein it is split into C₁-C₄ gases,naphtha, distillate and a 700° F.+ fraction.

[0062] The 700° F.+fraction is dewaxed, preferably in a catalyticdewaxing unit, or is both catalytically dewaxed and the product thensubjected to a low vacuum distillation, or fractionation, to produce alubricant, or lubricants. The lubricant, or lubricants, is of highviscosity index and low pour point, and is recovered in high yield.

[0063] In conducting the hydroisomerization step, the feed, at least 50percent, more preferably at least 70 percent, of which boils above 700°F., with hydrogen, is contacted and hydroisomerized over ahydroisomerization catalyst at hydroisomerization conditions sufficientto convert from about 20 percent to about 50 percent, preferably fromabout 30 to about 40 percent, of the 700° F.+ hydrocarbons of the feedto 700° F.− products, based on the weight of the total feed. At theseconversion levels, major amounts of the n-paraffins are hydroisomerized,or converted to isoparaffins, with minimal hydrocracking to gas and fuelby-products.

[0064] The total feed to the hydroisomerization reactor, whichconstitutes from about 20 percent to about 90 percent, preferably fromabout 30 percent to about 70 percent, by weight of the total liquidoutput from the F-T reactor, is fed, with hydrogen, into thehydroisomerization reactor. The hydroisomerization reactor contains abed of hydroisomerization catalyst with which the feed and hydrogen arecontacted; the catalyst comprising a metal hydrogenation ordehydrogenation component composited with an acidic oxide carrier, orsupport. In the hydroisomerization reactor, the feed introduced theretois thus converted to iso-paraffins and lower molecular weight speciesvia hydroisoomerization.

[0065] The hydrogenation or dehydrogenation metal component of thecatalyst used in the hydroisomerization reactor may be any Group VIIImetal of the Periodic Table of the Elements. Preferably the metal is anon-noble metal such as cobalt or nickel; with the preferred metal beingcobalt. The catalytically active metal may be present in the catalysttogether with one or more metal promoters or co-catalysts. The promotersmay be present as metals or as metal oxides, depending upon theparticular promoter. Suitable metal oxide promoters include oxides ofmetals from Group VI of the Periodic Table of the Elements. Preferably,the catalyst contains cobalt and molybdenum. The catalyst may alsocontain a hydrocracking suppressant since suppression of the crackingreaction is necessary. The hydrocracking suppressant may be either aGroup IB metal or a source of sulfur, usually in the form of a sulfidedcatalytically active metal, or a Group IB metal and a source of sulfur.

[0066] The acidic oxide carrier component of the hydroisomerizationcatalyst can be furnished by a support with which the catalytic metal ormetals can be composited by well known methods. The support can be anyacidic oxide or mixture of oxides or zeolites or mixtures thereof.Preferred supports include silica, alumina, silica-alumina,silica-alumina-phosphates, titania, zirconia, vanadia and other GroupIII, IV, V or VI oxides, as well as Y sieves, such as ultra stable Ysieves. Preferred supports include alumina and silica-alumina, morepreferably silica-alumina where the silica concentration of the bulksupport is less than about 50 wt. %, preferably less than about 35 wt.%. Most preferably the concentration ranges from about 15 wt. % to about30 wt. %. When alumina is used as the support, small amounts of chlorineor fluorine may be incorporated into the support to provide the acidfunctionality.

[0067] A preferred supported catalyst is one having surface areas in therange of about 180 to about 400 m²/gm, preferably about 230 to about 350m²/gm, and a pore volume of about 0.3 to about 1.0 mL/gm, preferablyabout 0.35 to about 0.75 mL/gm, a bulk density of about 0.5 to about 1.0g/mL, and a side crushing strength of about 0.8 to about 3.5 kg/mm.

[0068] The preparation of preferred amorphous silica-alumina micropheresfor use as supports is described in Ryland, Lloyd B., Tamele, M. W., andWilson, J. N., Cracking Catalysts, Catalysis; Volume VII, Ed. Paul H.Emmett, Reinhold Publishing Corporation, New York, 1960.

[0069] The hydroisomerization reactor is operated at conditions definedas follows: Major Operating Variables Typical Preferred Temperature, °C.200-450 290-400 Pressure, psig   300-10,000  500-1500 Hydrogen TreatRate, SCF/B  500-5000 1000-4000

[0070] During hydroisomerization, the amount of conversion of the 700°F.+ to 700° F.− is critical, and ranges from about 20 percent to about50 percent, preferably from about 30 to about 40 percent; and at theseconditions essentially all olefins and oxygenated products arehydrogenated.

[0071] The 700° F.+ fraction from the bottom of the fractionation columnis passed to a catalytic dewaxing unit wherein the waxy lubricantmolecules are subjected to a pour point reducing step to produce finalor near-final lubricants; some of which may require further separationin a lube vacuum pipe still. Thus, a lubricant from the catalystdewaxing unit can be passed to a low vacuum pipe still for furtherconcentration of lube molecules into a final product.

[0072] The final pour point reducing step in the catalyst dewaxing unitis preferably carried out by contact with a unitized mixed powder pelletcatalyst comprising a dehydrogenation component, a dewaxing component,and an isomerization component. The dehydrogenation component is acatalytically active metal, or metals, comprising a Group VIB, VIIB orGroup VIII metal of the Periodic Table of the Elements. The dewaxingcomponent is comprised of an intermediate or small pore crystallinezeolite, and the isomerization component is constituted of an amorphousacidic material. Such catalyst not only produces lubricants with highviscosity indexes and significantly reduced pour points but reducedyields of undesirable gas and naphtha.

[0073] Catalytic dewaxing is a process well documented in theliterature; as are catalysts useful in such processes. However, thepreferred catalysts employed in the catalytic dewaxing unit are unitizedmixed powder pellet catalysts characterized as particulate solidsparticles made by mixing together a powdered molecular sieve dewaxingcomponent and a powdered amorphous isomerization component, one or bothcomponents of which, preferably both, contains a dehydrogenationcomponent, or components, (or to which is subsequently added adehydrogenation component, or components), forming a homogeneous massfrom the mixture, and pelletizing the mass to produce solids particles,or pellets, each of which contains the dewaxing component, theisomerization component, and the dehydrogenation component in intimateadmixture; or contains the dewaxing component and the isomerizationcomponent to which is added the dehydroisomerization component, orcomponents, to form particulate solids wherein the dewaxing component,the isomerizing component, and hydrogenation components are present inintimate mixture. The components of the catalyst work together,cooperatively and synergistically, to selectively crack and convert then-paraffins, or waxy components of the feed, to produce reactionproducts which are removed from the process as gas, while allowingbranched hydrocarbons to pass downstream for removal as useful lube oilblending components, and lube oil products. This catalyst permits theconversion of Fischer-Tropsch reaction products to upgraded productsfrom which lubricants of high viscosity index and low pour point can berecovered. This objective, and others, is achieved while minimizing theproduction of the less desirable gas and naphtha.

[0074] In preparation of the unitized powder pellet catalyst, thecatalytic metal, or metals, dehydrogenation component can be compositedwith the dewaxing component, or the catalyst metal, or metals,dehydrogenation component can be composited with the isomerizationcomponent, or the catalytic metal, or metals, dehydrogenation componentcan be composited with both the dewaxing and the isomerizationcomponents prior to formation of the unitized powder pellet catalyst.The unitized powder pellet catalyst can also be formed from a compositeof the dewaxing and isomerization components and a catalytic metal, ormetals, dehydrogenation component can then be deposited thereon.Suitably, the dehydrogenation component is a Group VIB, Group VIIB, orGroup VIII metal, or metals, preferably a Group VIII noble metal, ormetals, of the Periodic Table of the Elements (Sargent-Welch ScientificCompany: Copyright 1968), suitably ruthenium, rhodium, palladium,osmium, iridium and platinum. Suitably, the catalytic metal, or metals,dehydrogenation component is present in concentration ranging from about0.1 percent to about 5.0 percent, preferably from about 0.1 percent toabout 3.0 percent, based on the weight of the total catalyst (drybasis). In general, the molecular sieve component is present in thecatalyst in concentrations ranging from about 2 percent to about 80percent, preferably from about 20 percent to about 60 percent, based onthe weight of the catalyst (dry basis). The isomerization component isgenerally present in concentration ranging from about 20 percent toabout 75 percent, preferably from about 30 percent to about 65 percent,based on the weight of the catalyst (dry basis).

[0075] The dewaxing component of the unitized powder pellet catalyst ispreferably an intermediate pore, or a small pore size molecular sieve,or zeolite. A preferred molecular sieve dewaxing component is anintermediate pore size zeolite having a 10 membered ring unidirectionalpore material which has oval 1-D pores having a minor axis between 4.2 Åand 4.8 Å and a major axis between 5.4 Å and 7 Å as determined by X-raycrystallography.

[0076] A yet more preferred dewaxing component used to form the unitizedpowder pellet catalyst is characterized as a small pore molecular sievewherein the pore windows are formed by 8 oxide atoms that form thelimiting edge of this pore window. The oxide atoms each constitute oneof the four oxide atoms of a tetrahedrally coordinated cluster around asilicon or aluminum ion, called a framework ion or atom. Each oxide ionis coordinated to two framework ions in these structures. The structureis referred to as “8 ring” as a shorthand way of describing a morecomplex structure; a shorthand notation used extensively in describingmolecular sieves of this type is the Atlas Of Zeolite Structure Types,Fourth Revised Edition 1996 in 8 Zeolites 17:1-230, 1996. Pores of thissize are such as to substantially exclude molecules of larger size thannormal hexane; or, conversely, to allow entry into the pores ofmolecules of smaller size than normal hexane. The small pore molecularsieve is of pore size ranging between about 6.3 Å and 2.3 Å, preferablyabout 5.1 Å to about 3.4 Å, and comprised of a crystalline tetrahedralframework oxide component. It is preferably selected from the groupconsisting of zeolites, tectosilicates, tetrahedral aluminophosphatesand tetrahedral silicoaluminophosphates (SAPOs). Exemplary of themolecular sieve components of this type are SAPO-56, (AFX), ZK-5 (KF1),AIPO₄-25 (ATV), Chabazite (CHA), TMA-E (EAB), Erionite (ERI), and LindeType A (LTA). The Linde Type A zeolite is a particularly preferredmolecular sieve.

[0077] The catalysts, besides the dewaxing, isomerization, anddehydrogenated components, may optionally also contain binder materials.Exemplary of such binder materials are silica, alumina, silica-alumina,clays, magnesia, titania, zirconia or mixtures of these with each otheror with other materials. Silica and alumina are preferred, with aluminabeing the most preferred binder. The binder, when present, is generallypresent in amount ranging from about 5 percent to about 50 percent,preferably from about 20 percent to about 30 percent, based on theweight of the total catalyst (dry basis; wt. %).

[0078] The unitized catalyst can be prepared by pulverizing andpowdering and then mixing together a powdered finished molecular sievecatalyst and a powdered finished isomerization catalyst, as components,and then compressing the homogeneous mass to form particulate solidshapes, e.g., lumpy solid shapes, extrudates, beads, pellets, pills,tablets or the like; each solid shape of which contains the molecularsieve dewaxing component, the isomerization component and thedehydrogenation component. One or more catalysts of given type can bepulverized and powdered, and mixed to provide a necessary component, orcomponents, of the unitized mixed pellet catalyst. For example, amolecular sieve catalyst can supply the dewaxing and dehydrogenatingfunctions, to wit: a molecular sieve component composited with,preferably by impregnation, a Group VIII metal, or metals, of thePeriodic Table, most preferably a Group VIII noble metal, or metals,e.g., platinum or palladium. Generally, the catalyst is impregnated withfrom about 0.1 percent to about 5.0 percent, preferably from about 0.1percent to about 3.0 percent, based on the weight of the catalyticcomponent (wt. %; dry basis).

[0079] The isomerization and dehydrogenation function, on the otherhand, can be supplied by an isomerization catalyst. Thus, theisomerization component of the catalyst is comprised of an amorphousacidic material; an isomerization catalyst comprised of an acidicsupport composited with a catalytically active metal, preferably a GroupVIII noble metal of the Periodic Table, suitably ruthenium, rhodium,palladium, osmium, iridium and platinum which can supply theisomerization and dehydrogenation functions. The isomerization catalystcomponent can thus be an isomerization catalyst such as those comprisinga refractory metal oxide support base (e.g., alumina, silica-alumina,zirconia, titanium, etc.) on which is deposited a catalytically activemetal selected from the group consisting of Group VIB, Group VIIB, GroupVIII metals and mixtures thereof, preferably Group VIII metals, morepreferably noble Group VIII metals, most preferably platinum orpalladium and optionally including a promoter or dopant such as halogen,phosphorus, boron, yttria, magnesia, etc. preferably halogen, yttria ormagnesia, most preferably fluorine. The catalytically active metals arepresent in the range of from about 0.1 to about 5.0 wt. %, preferablyfrom about 0.1 to about 2.0 wt. %. The promoters and dopants are used tocontrol the acidity of the isomerization catalyst. Thus, when theisomerization catalyst employs a base material such as alumina, acidityis imparted to the resultant catalyst by addition of a halogen,preferably fluorine. When a halogen is used, preferably fluorine, it ispresent in an amount in the range of about 0. 1 to about 10 wt. %,preferably about 0.1 to about 3 wt. %, more preferably from about 0.1 toabout 2 wt. % most preferably from about 0.5 to about 1.5 wt. %.Similarly, if silica-alumina is used as the base material, acidity canbe controlled by adjusting the ratio of silica to alumina or by adding adopant such as yttria or magnesia which reduces the acidity of thesilica-alumina base material as taught in U.S. Pat. No. 5,254,518(Soled, McVicker, Gates, Miseo). One or more isomerization catalysts canbe pulverized and powdered, and mixed to provide two of the necessarycomponents of the unitized mixed pellet catalyst.

[0080] Dewaxing is preferably carried out in the catalyst dewaxing unitin a slurry phase, or phase wherein the catalyst is dispersed throughoutand movable within a liquid paraffinic hydrocarbon oil. The 700° F.+feed is passed, with hydrogen, into the catalyst dewaxing unit andreaction carried out at catalytic dewaxing conditions tabulated asfollows: Major Operating Variable Typical Preferred Temperature, °F.(°C.) 300-840 (148-448) 500-752 (260-400) Pressure, psig  300-10,000 500-1500 Hydrogen Treat Rate, SCF/B 500-5000 1000-4000

[0081] The product of the catalyst dewaxing unit is generally a fullyconverted dewaxed lube oil blending component, or lube oil havingviscosity indexes ranging above about 110, and lube pour point belowabout −15° C.

[0082] The invention, and its principle of operation will be betterunderstood by reference to the following examples with illustratespecific and preferred embodiments, and comparative data. All parts arein terms of weight except as otherwise specified.

EXAMPLE 1 Extraction of Cobalt with a Sodium Salt of Ethylene DiamineTetraacetic Acid (EDTA)

[0083] A catalyst with 22 wt % Co on silica was prepared by impregnatinga particulate solids silica support twice with a solution ofCo(NO₃)₂.6H₂O (50 wt % in water). Using 120 ml of solution per 30 mlsupport, the cobalt loading achieved after the first impregnation wasless than 15 wt %. After drying/filtering the once-impregnated silicasupport, or precursor, was calcined for 5 hours at 250° C. to decomposethe nitrate into Co₃O₄ to prevent redissolution of the cobalt during thesecond impregnation step. The second through the fourth impregnationbrought the cobalt loading to 22 wt %. The precursor after eachimpregnation was dried and calcined at 250° C. for 5 hours.

[0084] Thirty ml of the resulting precursor was then slurried with 150ml of a 0.001 N aqueous solution of Na-EDTA. A pink to red coloration ofthe solution, a characteristic of the formation of a cobalt-EDTAcomplex, was observed in the extraction of each of Samples 2, 3 and 4;Sample 1 was not treated with Na-EDTA. Each sample was filtered, driedand analyzed for its cobalt content as given in Table 1. Table 1 alsogives the duration of the Na-EDTA extraction, illustrating the impact ofthe extraction time on the reduction of the cobalt loading: TABLE 1Duration of Sample # Extraction, Hours Co wt % Extent of Extraction, % 10 22 0 2 20 12 45 3 90 10 55 4 240 6 73

[0085] The data show that there was a rapid initial extraction of cobaltwhich slowed down significantly after the first 20 minutes. Thisphenomenon is characteristic of a diffusion limited extraction of thecobalt present in the pores whereas the cobalt near the outside surfaceof the precursor particle is readily redissolved.

[0086] The several catalyst precursors listed in Table 1, were nextreduced under hydrogen at 400° C. for 5 hours at 100 hr⁻¹ and thentested for hydrocarbon synthesis activity. The catalytic tests werecarried out in a down flow fixed bed unit operated: at atmosphericpressure, temperature of 190° to 195° C., GHSV=100 h⁻¹ and H₂:CO=2:1.The catalytic test sequence was carried out by increasing thetemperature until the maximum yield of C₅+ was reached. The activitiesmeasured as CO conversion are reported for the optimum temperature inTable 2. TABLE 2 Sample # Co % CO conv. % C₅+ Yield (g/m³) 1 22 65  80 212 68 110 3 10 69 115 4 6 72 120

[0087] The data reported in Table 2 show that higher activities and C₅+selectivities are obtained following progressive Na-EDTA treatments eventhough a significant amount of cobalt had been extracted. For example,comparing Sample 4 with Sample 1 shows that after removal of 73% of thecobalt originally present in the catalyst by the Na-EDTA treatment, theNa-EDTA treated catalyst is far more active (72 CO conv. % vis-a-vis 65CO conv. %) and selective (120 C₅+ g/m³ yield vis-a-vis 80 C₅+ g/m³yield) than the untreated catalyst albeit it contains only 27% as muchcobalt. The duration of the extraction thus not only controls the amountof cobalt extracted, but also improves the activity and selectivity ofthe extracted catalyst.

EXAMPLE 2 Extraction of Co Catalyst Precursor with EDTA/effect of PoreSizes

[0088] The extraction of Co with EDTA was applied to a series ofcatalysts precursors with various supports, pore sizes and loadings. Theextraction was carried out repeatedly slurrying the catalyst; 30 mlportions of the catalyst with 150 ml portions of a 0.001 N aqueoussolution of the Na-EDTA. The supports studied included different silicaswith an average pore size ranging from 11 to 52 Å and a silica-aluminawith a pore size of 30 Å. The catalytic tests were carried out accordingto the procedure described in Example 1. Table 3 summarizes the results.TABLE 3 Productivity Sample # Support Rp(Å) EDTA Co % Conversion % C₅+(g/m³) (g/g Co.h) (g/g Cat.h) 5a SiO₂ 11 no 6 12 8 — — 5b SiO₂ 11 yes 515 5 — — 6a SiO₂ 16 no 14 50 60 0.09 0.013 6b SiO₂ 16 yes 6 60 84 0.280.017 1 SiO₂ 35 no 22 65 80 0.090 0.018 4 SiO₂ 35 yes 6 72 120 0.4000.036 7a SiO₂ 52 no 26 42 40 0.04 0.008 7b SiO₂ 52 yes 7 36 21 0.060.004 8a SiO₂/Al₂O₃ 30 no 22 50 70 0.090 0.019 8b SiO₂/Al₂O₃ 30 yes 5 6290 0.400 0.021

[0089] From these data, it is readily apparent that both the activityand productivity of the catalysts for hydrogenating carbon monoxide isgenerally considerably higher after treatment with the Na-EDTA than isobtained with those catalysts which were not treated with the Na-EDTAdespite the fact that the former contained lesser amounts of cobalt.

EXAMPLE 3 Effect of Temperature in Conducting F-T Synthesis

[0090] Thirty ml of catalyst precursor containing 30 wt. % cobalt onsilica gel was slurried with 50 ml of 0.001 N Na-EDTA solution at 100°C. while continuously slurrying for 20 minutes. The solution was thendecanted, and this procedure was repeated three times giving a totalextraction time of 60 minutes using a total of 150 ml of Na-EDTAsolution.

[0091] Another extraction was carried out at similar conditions exceptthat it was conducted at an extraction temperature of 20° C.

[0092] The extracted catalysts, as well as an unextracted catalystprecursor, were reduced under H₂ at 400° C. for 5 hours at GHSV=100followed by Fischer-Tropsch synthesis testing at 190° C. using 2/1 H₂/COgas feed at GHSV=100 and atmospheric pressure. The results, given inTable 4, clearly show that improved C₅+ selectivity was obtained byconducting the extraction at the more elevated temperature. TABLE 4Extraction EDTA Temperature, °C. Treatment Wt. % Co % Conversion C₅+gm/m³ — None 30 73.8 88  20 Yes 26 76.4 89 100 Yes 10 73.8 115 

[0093] The hydrocarbons produced by a hydrocarbon synthesis processaccording to the invention are typically upgraded to more valuableproducts, by subjecting all or a portion of the C₅+ hydrocarbons tofractionation and/or conversion. By conversion is meant one or moreoperations in which the molecular structure of at least a portion of thehydrocarbon is changed and includes both noncatalytic processing (e.g.,steam cracking), and catalytic processing (e.g., catalytic cracking) inwhich a fraction is contacted with a suitable catalyst. If hydrogen ispresent as a reactant, such process steps are typically referred to ashydroconversion and include, for example, hydroisomerization,hydrocracking, hydrodewaxing, hydrorefining and the more severehydrorefining referred to as hydrotreating, all conducted at conditionswell known in the literature for hydroconversion of hydrocarbon feeds,including hydrocarbon feeds rich in paraffins. Illustrative, butnonlimiting examples of more valuable products formed by conversioninclude one or more of a synthetic crude oil, liquid fuel, olefins,solvents, lubricating, industrial or medicinal oil, waxy hydrocarbons,nitrogen and oxygen containing compounds, and the like. Liquid fuelincludes one or more of motor gasoline, diesel fuel, jet fuel, andkerosene, while lubricating oil includes, for example, automotive, jet,turbine and metal working oils. Industrial oil includes well drillingfluids, agricultural oils, heat transfer fluids and the like.

[0094] It is understood that various other embodiments and modificationsin the practice of the invention will be apparent to, and can be readilymade by, those skilled in the art without departing from the scope andspirit of the invention described above. Accordingly, it is not intendedthat the scope of the claims appended hereto be limited to the exactdescription set forth above, but rather that the claims be construed asencompassing all of the features of patentable novelty which reside inthe present invention, including all the features and embodiments whichwould be treated as equivalents thereof by those skilled in the art towhich the invention pertains.

Having described the invention, what is claimed is:
 1. A process for theactivation, or reactivation, of a catalyst comprising a powder orparticulate solids support, and an oxide, or oxides, of a metal, ormetals, catalytically active for conducting carbon monoxidehydrogenation reactions, which comprises contacting, and treating thecatalyst with a solution of a chelating compound sufficient to complexwith, extract and remove a portion of the metal, or metals, component ofthe oxide, or oxides, of the metal, or metals, from said catalyst, andreducing the residual metal, or metals components of the catalyst toactivate said catalyst in conducting hydrogenation of carbon monoxidereactions.
 2. The process of claim 1 wherein the support is a refractoryinorganic oxide, the catalytic metal, or metals, composited with thesupport is comprised of a Group VIII metal, from about 5 wt. percent toabout 70 wt. percent of the metal, or metals, is composited with thesupport, from about 1 percent to about 80 percent of the compositedmetal, or metals, is removed from the support by treatment with thesolution of chelating compound, and the activation, and reduction stepis carried out by contact of the catalyst with hydrogen.
 3. The processof claim 1 wherein the powder, or support is a refractory inorganicoxide, the catalytic metal, or metals, composited with the powder, orsupport is comprised of a Group VIII metal, from about 10 wt. percent toabout 30 wt. percent of the metal, or metals, is composited with thepowder or support, from about 25 percent to about 75 percent of thecomposited metal, or metals, is removed from the powder, or support bytreatment with the solution of chelating compound, and the activation,and reduction step is carried out by contact of the catalyst withhydrogen.
 4. The process of claim 1 wherein the powder, or support is acrystalline aluminosilicate zeolite, natural or synthetic.
 5. Theprocess of claim 4 wherein the crystalline aluminosilicate zeolite is anA zeolite, X zeolite, Y zeolite, mordenite, ZSM-zeolite, silicalite,MCM, ALPO, or SAPO type zeolite.
 6. The process of claim 1 wherein thepowder, or support is a refractory inorganic oxide of average poreradius below about 100 Å.
 7. The process of claim 6 wherein the averagepore radius of the powder, or support ranges from about 15 Å to about 40Å.
 8. The process of claim 7 wherein the average pore radius of thepowder, or support ranges from about 20 Å to about 35 Å.
 9. The processof claim 1 wherein the chelating compound has a denticity of six, andcomprises a nitrogen or oxygen containing compound, or nitrogen andoxygen containing compound.
 10. The process of claim 1 wherein the sotreated catalyst is prepared ab initio by the steps comprisingcontacting, in one or more steps, a powder, or preformed, particulatesolids support with a liquid, or solution in which there is dispersed ordissolved a compound, or salt of a metal, or metals, catalyticallyactive for conducting carbon monoxide hydrogenation reactions, toimpregnate and deposit said metal, or metals, upon said powder, orsupport, and calcining said powder, or support following eachimpregnation step to form an oxide, or oxides, of the deposited metal,or metals.
 11. The process of claim 10 wherein the catalytically activemetal component of the catalyst is comprised of cobalt.
 12. The processof claim 11 wherein the catalytically active metallic component of thecatalyst is oxidized and calcined by contact with an oxidizingatmosphere at temperatures ranging from about 100° C. to about 700° C.and converted to an oxide.
 13. The process of claim 10 wherein informing the catalyst from about 5 wt. percent to about 70 wt. percent ofthe catalytic metal, as elemental metal, is composited with the powder,or solids support, the catalytic metal comprises cobalt, and the powder,or solids support comprises silica, silica-alumina, titania, or azeolite, natural or synthetic.
 14. The process of claim 13 wherein thecatalyst is contacted with a solution of a chelating compound sufficientto complex with, extract and remove from about 1 percent to about 80percent of the composited cobalt metal component from the powder, orsupport, the catalyst then calcined, and the catalyst then activated andreduced by contact with hydrogen.
 15. The process of claim 14 whereinfrom about 25 percent to about 75 percent of the composited metal isremoved from the powder, or support by contact and treatment with thesolution of the chelating compound.
 16. The process of claim 14 whereinthe catalyst contacted with the solution of chelating compound iscomprised of cobalt promoted with rhenium.
 17. The process of claim 16wherein the catalyst is comprised of cobalt promoted with ruthenium. 18.A catalyst comprising a powder, or particulate solids support, and anoxide, or oxides, of a metal, or metals, catalytically active forconducting carbon monoxide hydrogenation reactions made in a process ascharacterized by any of claims 1 through
 17. 19. A process useful forconducting carbon monoxide hydrogenation reactions by contact atreaction conditions with a catalyst comprising a powder, or particulatesolids support, and an oxide, or oxides, of a metal, or metals,catalytically active for conducting said carbon monoxide hydrogenationreactions made by the steps comprising a process as characterized by anyof claims 1 through
 17. 20. A process wherein C₅+ hydrocarbons areproduced from carbon monoxide and hydrogen by contact at reactionconditions with a catalyst comprising a powder, or particulate solidssupport, and an oxide, or oxides, of a metal, or metals, catalyticallyactive for conducting carbon monoxide hydrogenation reactions made bythe steps comprising a process as characterized by any of claims 1through 17, and all or a portion of the C₅+ hydrocarbons produced bysaid process are upgraded to more valuable products by fractionationand/or a conversion operation.
 21. A product comprising a hydrocarbonobtained by converting a mixture of hydrogen and carbon monoxide via acarbon monoxide hydrogenation reaction by contact, at reactionconditions, with a catalyst comprising a powder, or particulate solidssupport, and a metal, or metals, catalytically active for conductingsaid carbon monoxide hydrogenation reactions, made by the steps of aprocess characterized by any of claims 1 through
 17. 22. A C₅+hydrocarbon product obtained by converting a mixture of hydrogen andcarbon monoxide via a carbon monoxide hydrogenation reaction by contact,at reaction conditions, with a catalyst comprising a powder, orparticulate solids support, and a metal, or metals, catalytically activefor conducting said carbon monoxide hydrogenation reactions, made by thesteps of a process characterized by any of claims 1 through
 17. 23. Ahydrocarbon distillate product suitable for use as a transportation fuelwhich is produced by upgrading a hydrocarbon product obtained byconverting a mixture of hydrogen and carbon monoxide via a carbonmonoxide hydrogenation reaction by contact, at reaction conditions, witha catalyst comprising a powder, or particulate solids support, and ametal, or metals, catalytically active for conducting said carbonmonoxide hydrogenation reactions, made by the steps of a processcharacterized by any of claims 1 through
 17. 24. A lube oil, lube oilblending component, or lube oil base stock which is produced byupgrading a hydrocarbon product obtained by converting a mixture ofhydrogen and carbon monoxide via a carbon monoxide hydrogenationreaction by contact, at reaction conditions, with a catalyst comprisinga powder, or particulate solids support, and a metal, or metals,catalytically active for conducting said carbon monoxide hydrogenationreactions, made by the steps of a process characterized by any of claims1 through
 17. 25. A C₅+ hydrocarbon oil suitable as, or for use in theproduction of a drilling mud, technical or medicinal grade white oil,solvent, chemical raw material, monomer, polymer, emulsion, or specialtyproduct produced by upgrading a hydrocarbon product obtained byconverting a mixture of hydrogen and carbon monoxide via a carbonmonoxide hydrogenation reaction by contact, at reaction conditions, witha catalyst comprising a powder, or particulate solids support, and ametal, or metals, catalytically active for conducting said carbonmonoxide hydrogenation reactions, made by the steps of a processcharacterized by any of claims 1 through 17.